Nanotechnology provides techniques or processes for fabricating structures, devices, and systems with features at a molecular or atomic scale, e.g., structures in a range of one to hundreds of nanometers in some applications. For example, nanoscale materials can be configured to sizes similar to some large molecules, e.g., including biomolecules such as enzymes. These nanoscale materials are used to create a nanostructure, nanodevice, or a nanosystem that can exhibit various unique properties that are not present in the same materials at larger dimensions, and such unique properties of the nanoscale materials can be exploited for a wide range of applications, e.g., including the sensing of chemical or biological substances.
Chemical or biological sensors are analytical tools that can detect a chemical, substance, or organism using a sensing component coupled with a transducing element to convert a detection event into a signal for processing and/or display. For example, molecular sensors can be configured to use specific chemical properties or molecular recognition mechanisms to identify target molecular agents. The sensor can use the transducer element to transform a signal resulting from the detection of the molecular analyte by the sensing component into a different signal that can be addressed by a suitable transduction mechanism, for example, electrical, magnetic, mechanical, physicochemical, electrochemical, optical, piezoelectric, or others.
Raman spectroscopy is a quantitative and nondestructive optical technique based on inelastic scattering of photons by molecular vibrations of materials (e.g., such as biopolymers) that is capable of detecting information on the biochemical composition of cells (e.g., amino acids and proteins, lipids, and nucleic acids, among others). For example, Raman spectroscopy can be used as a bio-characterization and analysis tool to study cellular events, e.g., such as chemical changes and cell death induced by drugs or toxins, as well as cellular changes at different time points in the cell cycle. Raman spectroscopy can provide data related to physiological processes occurring within a cell without the use of chemical tags, leaving cellular functions unaltered during observations and available for repeated monitoring of time-dependent events of the same cell.